A crisp white light tends to render skin tones most accurately. Halogen bulbs set the gold standard. Low-voltage varieties (with a built-in transformer that converts 120 volts to 12 volts) are especially compact, and the smaller bulb gives a nice sparkling effect. Halogen bulbs cost a few dollars more than standard incandescents but can last three times as long. Many feature screw-in bases; those labeled medium-base (MB) are shaped like standard incandescents, so they fit most fixtures. The newest compact fluorescent bulbs also offer good color rendering and are up to 10 times more efficient than regular incandescent bulbs.
These are a lighting designer's best friend because they grant absolute control over the lighting, and thus the mood, of the room. In a very small space like a powder room, dimming the vanity fixtures might even provide all-in-one task, ambient, and accent lighting. Plus, dimmers conserve energy. The total savings depends on how much you dim the bulb, but one dimmed just 10 percent will last twice as long as a bulb at full brightness.
Today's dimmers work for every kind of light source, though you need to know what to ask for. A 120-volt incandescent or halogen light source will need an incandescent dimmer, while low-voltage and fluorescent fixtures require their own compatible dimmers. Occasionally, dimmed bulbs will buzz as the filament vibrates. Switching to a lower-watt bulb (which has a smaller filament) should reduce or even eliminate the noise.
Attention to aesthetics in the bathroom doesn't diminish the importance of safety. Electricity and water are still lethal companions, and nowhere do they mingle more closely than in the bathroom. Always consult a certified electrician before tackling even the simplest lighting project.
The National Electric Code requires all new outlets to have GFCIs, ground-fault circuit interrupters; the newer ones can be retrofitted to existing outlets. Even with a GFCI, freestanding plug-in lamps should never be placed near a sink or tub. Fixtures that are going to be within a certain distance of the tub or shower (usually 6 feet, though local codes vary) must be "wet" or "shower-location" rated. Don't confuse this with the less rigorous "damp-location" rating that's ascribed to most outdoor lighting.